Administration of the MapR-DB is done primarily via the command line (maprcli) or with the MapR Control System (MCS). Regardless of whether the MapR-DB table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter options. MapR-DB administration is associated with tables, columns and column families, and table regions.

Metrics are collected from each node in the cluster so that administrators can use the data to monitor the cluster. In general, the collectd service collects metrics every 10 seconds. The exception is volume metrics which are collected every 10 minutes.

By default, the OpenTSDB service is configured to use a default heap size of 2 gigabytes (recommended size is 6 gigabytes). You can edit the warden.opentsdb.conf file on each node to override the default value.

Fluentd collects log events from each node in the cluster and stores them in a centralized location so that administrators can search the logs when troubleshooting issues in the cluster. The process that fluentd uses to parse and send log events to Elasticsearch differs based on the formatting of log events in each log file.

When you add services to a cluster where MapR Monitoring is already configured, you must restart collectd and Fluentd services to enable the collection of logs and metrics for the newly added services.

The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.

Reconfiguring MapR Monitoring

Changes to an existing cluster, such as the addition of services, may require
additional steps to enable the collection of metrics and logs.

Configure Monitoring for Additional ServicesWhen you add services to a cluster where MapR Monitoring is already configured, you must restart collectd and Fluentd services to enable the collection of logs and metrics for the newly added services.

Update the Monitoring Storage NodesYou must reconfigure MapR Monitoring when you add additional OpenTSDB or Elasticsearch nodes or when you change the OpenTSDB or Elasticsearch node locations.